What is the recommended regimen for malaria prophylaxis?

Malaria Prophylaxis Recommendations

First-Line Drug Selection Based on Geographic Resistance

For chloroquine-resistant areas (most of sub-Saharan Africa and many other endemic regions), choose from three first-line options: atovaquone-proguanil, doxycycline 100 mg daily, or mefloquine 250 mg weekly. 1

Chloroquine-Sensitive Areas

• Use chloroquine 300 mg base weekly for the rare chloroquine-sensitive regions (Haiti, Central America west of Panama Canal, and limited Middle Eastern areas) 1, 2
• Hydroxychloroquine is interchangeable with chloroquine at equivalent doses in these areas 3

Chloroquine-Resistant Areas (Most of Africa, Asia, South America)

Select based on the following patient-specific algorithm:

Atovaquone-proguanil (Malarone):

• Best choice for short-term travelers who want minimal pre- and post-travel dosing 1
• Start 1-2 days before travel, continue daily during travel, stop only 7 days after departure (shortest post-exposure duration) 1
• Adult dose: 250 mg atovaquone/100 mg proguanil daily 4
• Advantages: Shortest post-travel duration, well-tolerated, can be used in all ages if weight >5 kg 1

Doxycycline 100 mg daily:

• Best choice for cost-conscious travelers and those going to mefloquine-resistant areas (Thailand-Myanmar-Cambodia border regions) 1, 5
• Start 1-2 days before travel, continue daily, continue for 4 weeks after departure 5, 4
• Contraindicated in pregnancy and children <8 years due to tooth discoloration and bone growth inhibition 5
• Critical warning: Causes severe photosensitivity—patients must use high-SPF sunscreen, protective clothing, and avoid excessive sun exposure 5

Mefloquine 250 mg weekly:

• Start 1-2 weeks before travel (allows time to assess tolerance), continue weekly, continue for 4 weeks after departure 1
• Avoid in patients with seizure history, psychiatric disorders (depression, anxiety, psychosis), or occupations requiring fine motor coordination (pilots, divers) 1
• 70% of neuropsychiatric side effects occur in first three doses—discontinue immediately if severe mood changes, hallucinations, or seizures develop 1

Critical Timing Requirements

Never stop prophylaxis early—this is the most common cause of preventable malaria deaths in travelers: 3

• Chloroquine/mefloquine: Continue for full 4 weeks after leaving endemic area 1
• Doxycycline: Continue for full 4 weeks after leaving endemic area 5, 4
• Atovaquone-proguanil: Continue for only 7 days after leaving endemic area 1

Special Populations

Pregnant Women

• Chloroquine is the safest option in pregnancy 1
• Carry standby Fansidar (sulfadoxine-pyrimethamine) for presumptive self-treatment if fever develops and medical care is unavailable 1
• Doxycycline is absolutely contraindicated in pregnancy 5
• Mefloquine can be used in second and third trimesters if chloroquine-resistant area and no alternatives 1

Children

• Children <15 kg: Use chloroquine as first choice 1
• Children >8 years and >15 kg: Can use any adult option with weight-based dosing 1
• Children <8 years: Doxycycline is contraindicated 5
• Doxycycline dosing for children >8 years: 2 mg/kg daily (maximum 100 mg/day) 4

Long-Term Travelers (>6 months)

• Doxycycline or atovaquone-proguanil are preferred over mefloquine for extended use 1
• Hydroxychloroquine requires periodic ophthalmologic examinations if used for >6 years cumulative exposure due to retinopathy risk 3

Prevention of Relapsing Malaria (P. vivax and P. ovale)

For travelers with prolonged exposure to P. vivax or P. ovale endemic areas (Southeast Asia, Central/South America, parts of Africa), add primaquine 30 mg base daily during the last 2 weeks of the 4-week post-exposure prophylaxis period 1, 5

Mandatory G6PD testing before primaquine use:

• Primaquine causes potentially severe hemolysis in G6PD-deficient patients 1, 5
• Contraindicated in pregnancy 1, 5

Essential Non-Pharmacologic Measures

Chemoprophylaxis alone is insufficient—combine with mosquito avoidance measures: 1

• Remain in well-screened areas between dusk and dawn (peak Anopheles feeding time) 1
• Apply DEET-containing repellents (20-50% concentration) to exposed skin 1
• Wear long sleeves and pants after sunset 1
• Sleep under permethrin-treated bed nets 1
• Apply permethrin spray to clothing and gear 1

Common Pitfalls to Avoid

Most malaria deaths in travelers occur due to non-compliance with prophylaxis regimens—emphasize starting 1-2 weeks before travel (for chloroquine/mefloquine) and continuing for the full post-exposure period 3

No prophylactic regimen provides 100% protection—instruct patients to seek immediate medical evaluation if fever develops during or after travel, even if fully compliant with prophylaxis 3, 2

Mefloquine neuropsychiatric effects are unpredictable—screen carefully for contraindications and provide clear instructions to discontinue immediately if mood changes occur 1